20,928 research outputs found
Understanding user experience of mobile video: Framework, measurement, and optimization
Since users have become the focus of product/service design in last decade, the term User eXperience (UX) has been frequently used in the field of Human-Computer-Interaction (HCI). Research on UX facilitates a better understanding of the various aspects of the user’s interaction with the product or service. Mobile video, as a new and promising service and research field, has attracted great attention. Due to the significance of UX in the success of mobile video (Jordan, 2002), many researchers have centered on this area, examining users’ expectations, motivations, requirements, and usage context. As a result, many influencing factors have been explored (Buchinger, Kriglstein, Brandt & Hlavacs, 2011; Buchinger, Kriglstein & Hlavacs, 2009). However, a general framework for specific mobile video service is lacking for structuring such a great number of factors. To measure user experience of multimedia services such as mobile video, quality of experience (QoE) has recently become a prominent concept. In contrast to the traditionally used concept quality of service (QoS), QoE not only involves objectively measuring the delivered service but also takes into account user’s needs and desires when using the service, emphasizing the user’s overall acceptability on the service. Many QoE metrics are able to estimate the user perceived quality or acceptability of mobile video, but may be not enough accurate for the overall UX prediction due to the complexity of UX. Only a few frameworks of QoE have addressed more aspects of UX for mobile multimedia applications but need be transformed into practical measures. The challenge of optimizing UX remains adaptations to the resource constrains (e.g., network conditions, mobile device capabilities, and heterogeneous usage contexts) as well as meeting complicated user requirements (e.g., usage purposes and personal preferences). In this chapter, we investigate the existing important UX frameworks, compare their similarities and discuss some important features that fit in the mobile video service. Based on the previous research, we propose a simple UX framework for mobile video application by mapping a variety of influencing factors of UX upon a typical mobile video delivery system. Each component and its factors are explored with comprehensive literature reviews. The proposed framework may benefit in user-centred design of mobile video through taking a complete consideration of UX influences and in improvement of mobile videoservice quality by adjusting the values of certain factors to produce a positive user experience. It may also facilitate relative research in the way of locating important issues to study, clarifying research scopes, and setting up proper study procedures. We then review a great deal of research on UX measurement, including QoE metrics and QoE frameworks of mobile multimedia. Finally, we discuss how to achieve an optimal quality of user experience by focusing on the issues of various aspects of UX of mobile video. In the conclusion, we suggest some open issues for future study
On Factors Affecting the Usage and Adoption of a Nation-wide TV Streaming Service
Using nine months of access logs comprising 1.9 Billion sessions to BBC
iPlayer, we survey the UK ISP ecosystem to understand the factors affecting
adoption and usage of a high bandwidth TV streaming application across
different providers. We find evidence that connection speeds are important and
that external events can have a huge impact for live TV usage. Then, through a
temporal analysis of the access logs, we demonstrate that data usage caps
imposed by mobile ISPs significantly affect usage patterns, and look for
solutions. We show that product bundle discounts with a related fixed-line ISP,
a strategy already employed by some mobile providers, can better support user
needs and capture a bigger share of accesses. We observe that users regularly
split their sessions between mobile and fixed-line connections, suggesting a
straightforward strategy for offloading by speculatively pre-fetching content
from a fixed-line ISP before access on mobile devices.Comment: In Proceedings of IEEE INFOCOM 201
MSPlayer: Multi-Source and multi-Path LeverAged YoutubER
Online video streaming through mobile devices has become extremely popular
nowadays. YouTube, for example, reported that the percentage of its traffic
streaming to mobile devices has soared from 6% to more than 40% over the past
two years. Moreover, people are constantly seeking to stream high quality video
for better experience while often suffering from limited bandwidth. Thanks to
the rapid deployment of content delivery networks (CDNs), popular videos are
now replicated at different sites, and users can stream videos from close-by
locations with low latencies. As mobile devices nowadays are equipped with
multiple wireless interfaces (e.g., WiFi and 3G/4G), aggregating bandwidth for
high definition video streaming has become possible.
We propose a client-based video streaming solution, MSPlayer, that takes
advantage of multiple video sources as well as multiple network paths through
different interfaces. MSPlayer reduces start-up latency and provides high
quality video streaming and robust data transport in mobile scenarios. We
experimentally demonstrate our solution on a testbed and through the YouTube
video service.Comment: accepted to ACM CoNEXT'1
Saving Energy in Mobile Devices for On-Demand Multimedia Streaming -- A Cross-Layer Approach
This paper proposes a novel energy-efficient multimedia delivery system
called EStreamer. First, we study the relationship between buffer size at the
client, burst-shaped TCP-based multimedia traffic, and energy consumption of
wireless network interfaces in smartphones. Based on the study, we design and
implement EStreamer for constant bit rate and rate-adaptive streaming.
EStreamer can improve battery lifetime by 3x, 1.5x and 2x while streaming over
Wi-Fi, 3G and 4G respectively.Comment: Accepted in ACM Transactions on Multimedia Computing, Communications
and Applications (ACM TOMCCAP), November 201
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